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<a href="#pub-attribs">Data Fields</a>  </div>
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<div class="title">MQTTClient_message Struct Reference</div>  </div>
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<p>A structure representing the payload and attributes of an MQTT message.  
 <a href="structMQTTClient__message.html#details">More...</a></p>

<p><code>#include &lt;MQTTClient.h&gt;</code></p>
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Collaboration diagram for MQTTClient_message:</div>
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<div class="center"><img src="structMQTTClient__message__coll__graph.png" border="0" usemap="#MQTTClient__message_coll__map" alt="Collaboration graph"/></div>
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<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-attribs"></a>
Data Fields</h2></td></tr>
<tr class="memitem:a7f5160eeef15b17f7c8ac493015f558d"><td class="memItemLeft" align="right" valign="top">char&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#a7f5160eeef15b17f7c8ac493015f558d">struct_id</a> [4]</td></tr>
<tr class="memdesc:a7f5160eeef15b17f7c8ac493015f558d"><td class="mdescLeft">&#160;</td><td class="mdescRight">The eyecatcher for this structure.  <a href="structMQTTClient__message.html#a7f5160eeef15b17f7c8ac493015f558d">More...</a><br /></td></tr>
<tr class="separator:a7f5160eeef15b17f7c8ac493015f558d"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a27b983a1ac95eb5c335d40840129c0c8"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#a27b983a1ac95eb5c335d40840129c0c8">struct_version</a></td></tr>
<tr class="memdesc:a27b983a1ac95eb5c335d40840129c0c8"><td class="mdescLeft">&#160;</td><td class="mdescRight">The version number of this structure.  <a href="structMQTTClient__message.html#a27b983a1ac95eb5c335d40840129c0c8">More...</a><br /></td></tr>
<tr class="separator:a27b983a1ac95eb5c335d40840129c0c8"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a85b39bde61ef9f5ed853ad6489145a94"><td class="memItemLeft" align="right" valign="top"><a id="a85b39bde61ef9f5ed853ad6489145a94"></a>
int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#a85b39bde61ef9f5ed853ad6489145a94">payloadlen</a></td></tr>
<tr class="memdesc:a85b39bde61ef9f5ed853ad6489145a94"><td class="mdescLeft">&#160;</td><td class="mdescRight">The length of the MQTT message payload in bytes. <br /></td></tr>
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<tr class="memitem:a90437a223f235ad4412d0c7c69f08125"><td class="memItemLeft" align="right" valign="top"><a id="a90437a223f235ad4412d0c7c69f08125"></a>
void *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#a90437a223f235ad4412d0c7c69f08125">payload</a></td></tr>
<tr class="memdesc:a90437a223f235ad4412d0c7c69f08125"><td class="mdescLeft">&#160;</td><td class="mdescRight">A pointer to the payload of the MQTT message. <br /></td></tr>
<tr class="separator:a90437a223f235ad4412d0c7c69f08125"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ab981c28422ec70dbf8127a4f7164d964"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#ab981c28422ec70dbf8127a4f7164d964">qos</a></td></tr>
<tr class="memdesc:ab981c28422ec70dbf8127a4f7164d964"><td class="mdescLeft">&#160;</td><td class="mdescRight">The quality of service (QoS) assigned to the message.  <a href="structMQTTClient__message.html#ab981c28422ec70dbf8127a4f7164d964">More...</a><br /></td></tr>
<tr class="separator:ab981c28422ec70dbf8127a4f7164d964"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:aad83220f265db124174ad79f528bb367"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#aad83220f265db124174ad79f528bb367">retained</a></td></tr>
<tr class="memdesc:aad83220f265db124174ad79f528bb367"><td class="mdescLeft">&#160;</td><td class="mdescRight">The retained flag serves two purposes depending on whether the message it is associated with is being published or received.  <a href="structMQTTClient__message.html#aad83220f265db124174ad79f528bb367">More...</a><br /></td></tr>
<tr class="separator:aad83220f265db124174ad79f528bb367"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:abbb5f23377bd9f39cc79756786fa45cc"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#abbb5f23377bd9f39cc79756786fa45cc">dup</a></td></tr>
<tr class="memdesc:abbb5f23377bd9f39cc79756786fa45cc"><td class="mdescLeft">&#160;</td><td class="mdescRight">The dup flag indicates whether or not this message is a duplicate.  <a href="structMQTTClient__message.html#abbb5f23377bd9f39cc79756786fa45cc">More...</a><br /></td></tr>
<tr class="separator:abbb5f23377bd9f39cc79756786fa45cc"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a3be81df63644606036c0a139564a1d92"><td class="memItemLeft" align="right" valign="top"><a id="a3be81df63644606036c0a139564a1d92"></a>
int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#a3be81df63644606036c0a139564a1d92">msgid</a></td></tr>
<tr class="memdesc:a3be81df63644606036c0a139564a1d92"><td class="mdescLeft">&#160;</td><td class="mdescRight">The message identifier is normally reserved for internal use by the MQTT client and server. <br /></td></tr>
<tr class="separator:a3be81df63644606036c0a139564a1d92"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:aa24d24d388481c0616a704cabb041f95"><td class="memItemLeft" align="right" valign="top"><a id="aa24d24d388481c0616a704cabb041f95"></a>
<a class="el" href="structMQTTProperties.html">MQTTProperties</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structMQTTClient__message.html#aa24d24d388481c0616a704cabb041f95">properties</a></td></tr>
<tr class="memdesc:aa24d24d388481c0616a704cabb041f95"><td class="mdescLeft">&#160;</td><td class="mdescRight">The MQTT V5 properties associated with the message. <br /></td></tr>
<tr class="separator:aa24d24d388481c0616a704cabb041f95"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>A structure representing the payload and attributes of an MQTT message. </p>
<p>The message topic is not part of this structure (see <a class="el" href="MQTTClient_8c.html#a5e0cfa14237d7557bee2a59747ecadd3" title="This function attempts to publish a message to a given topic (see also MQTTClient_publish()).">MQTTClient_publishMessage()</a>, <a class="el" href="MQTTClient_8c.html#a3cd7a94b48d1d9c6b8af4b9203d69d37" title="This function attempts to publish a message to a given topic (see also MQTTClient_publishMessage()).">MQTTClient_publish()</a>, <a class="el" href="MQTTClient_8c.html#a4c2df88d00a3dadd510a8cb774739366" title="This function performs a synchronous receive of incoming messages.">MQTTClient_receive()</a>, <a class="el" href="MQTTClient_8c.html#a2bc00ce11e0cac5dbc0938c512b4ab31" title="This function frees memory allocated to an MQTT message, including the additional memory allocated to...">MQTTClient_freeMessage()</a> and MQTTClient_messageArrived()). </p>
</div><h2 class="groupheader">Field Documentation</h2>
<a id="abbb5f23377bd9f39cc79756786fa45cc"></a>
<h2 class="memtitle"><span class="permalink"><a href="#abbb5f23377bd9f39cc79756786fa45cc">&#9670;&nbsp;</a></span>dup</h2>

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<p>The dup flag indicates whether or not this message is a duplicate. </p>
<p>It is only meaningful when receiving QoS1 messages. When true, the client application should take appropriate action to deal with the duplicate message. </p>

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<h2 class="memtitle"><span class="permalink"><a href="#ab981c28422ec70dbf8127a4f7164d964">&#9670;&nbsp;</a></span>qos</h2>

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<p>The quality of service (QoS) assigned to the message. </p>
<p>There are three levels of QoS: </p><dl>
<dt><b>QoS0</b> </dt>
<dd>Fire and forget - the message may not be delivered </dd>
<dt><b>QoS1</b> </dt>
<dd>At least once - the message will be delivered, but may be delivered more than once in some circumstances. </dd>
<dt><b>QoS2</b> </dt>
<dd>Once and one only - the message will be delivered exactly once. </dd>
</dl>

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<h2 class="memtitle"><span class="permalink"><a href="#aad83220f265db124174ad79f528bb367">&#9670;&nbsp;</a></span>retained</h2>

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<p>The retained flag serves two purposes depending on whether the message it is associated with is being published or received. </p>
<p><b>retained = true</b><br  />
 For messages being published, a true setting indicates that the MQTT server should retain a copy of the message. The message will then be transmitted to new subscribers to a topic that matches the message topic. For subscribers registering a new subscription, the flag being true indicates that the received message is not a new one, but one that has been retained by the MQTT server.</p>
<p><b>retained = false</b> <br  />
 For publishers, this indicates that this message should not be retained by the MQTT server. For subscribers, a false setting indicates this is a normal message, received as a result of it being published to the server. </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a7f5160eeef15b17f7c8ac493015f558d">&#9670;&nbsp;</a></span>struct_id</h2>

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          <td class="memname">char MQTTClient_message::struct_id[4]</td>
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<p>The eyecatcher for this structure. </p>
<p>must be MQTM. </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a27b983a1ac95eb5c335d40840129c0c8">&#9670;&nbsp;</a></span>struct_version</h2>

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<p>The version number of this structure. </p>
<p>Must be 0 or 1 0 indicates no message properties </p>

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<hr/>The documentation for this struct was generated from the following file:<ul>
<li>MQTTClient.h</li>
</ul>
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